package keeper

import (
	"github.com/CosmWasm/wasmd/x/wasm/internal/types"
	wasmvmtypes "github.com/CosmWasm/wasmvm/types"
	sdk "github.com/cosmos/cosmos-sdk/types"
	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
)

// OnOpenChannel calls the contract to participate in the IBC channel handshake step.
// In the IBC protocol this is either the `Channel Open Init` event on the initiating chain or
// `Channel Open Try` on the counterparty chain.
// Protocol version and channel ordering should be verified for example.
// See https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#channel-lifecycle-management
func (k Keeper) OnOpenChannel(
	ctx sdk.Context,
	contractAddr sdk.AccAddress,
	channel wasmvmtypes.IBCChannel,
) error {
	_, codeInfo, prefixStore, err := k.contractInstance(ctx, contractAddr)
	if err != nil {
		return err
	}

	env := types.NewEnv(ctx, contractAddr)
	querier := QueryHandler{
		Ctx:     ctx,
		Plugins: k.queryPlugins,
	}

	gas := gasForContract(ctx)
	gasUsed, execErr := k.wasmer.IBCChannelOpen(codeInfo.CodeHash, env, channel, prefixStore, cosmwasmAPI, querier, ctx.GasMeter(), gas)
	consumeGas(ctx, gasUsed)
	if execErr != nil {
		return sdkerrors.Wrap(types.ErrExecuteFailed, execErr.Error())
	}

	return nil
}

// OnConnectChannel calls the contract to let it know the IBC channel was established.
// In the IBC protocol this is either the `Channel Open Ack` event on the initiating chain or
// `Channel Open Confirm` on the counterparty chain.
//
// There is an open issue with the [cosmos-sdk](https://github.com/cosmos/cosmos-sdk/issues/8334)
// that the counterparty channelID is empty on the initiating chain
// See https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#channel-lifecycle-management
func (k Keeper) OnConnectChannel(
	ctx sdk.Context,
	contractAddr sdk.AccAddress,
	channel wasmvmtypes.IBCChannel,
) error {
	contractInfo, codeInfo, prefixStore, err := k.contractInstance(ctx, contractAddr)
	if err != nil {
		return err
	}

	env := types.NewEnv(ctx, contractAddr)
	querier := QueryHandler{
		Ctx:     ctx,
		Plugins: k.queryPlugins,
	}

	gas := gasForContract(ctx)
	res, gasUsed, execErr := k.wasmer.IBCChannelConnect(codeInfo.CodeHash, env, channel, prefixStore, cosmwasmAPI, querier, ctx.GasMeter(), gas)
	consumeGas(ctx, gasUsed)
	if execErr != nil {
		return sdkerrors.Wrap(types.ErrExecuteFailed, execErr.Error())
	}

	// emit all events from this contract itself
	events := types.ParseEvents(res.Attributes, contractAddr)
	ctx.EventManager().EmitEvents(events)

	if err := k.messenger.Dispatch(ctx, contractAddr, contractInfo.IBCPortID, res.Messages...); err != nil {
		return err
	}
	return nil
}

// OnCloseChannel calls the contract to let it know the IBC channel is closed.
// Calling modules MAY atomically execute appropriate application logic in conjunction with calling chanCloseConfirm.
//
// Once closed, channels cannot be reopened and identifiers cannot be reused. Identifier reuse is prevented because
// we want to prevent potential replay of previously sent packets
// See https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#channel-lifecycle-management
func (k Keeper) OnCloseChannel(
	ctx sdk.Context,
	contractAddr sdk.AccAddress,
	channel wasmvmtypes.IBCChannel,
) error {
	contractInfo, codeInfo, prefixStore, err := k.contractInstance(ctx, contractAddr)
	if err != nil {
		return err
	}

	params := types.NewEnv(ctx, contractAddr)
	querier := QueryHandler{
		Ctx:     ctx,
		Plugins: k.queryPlugins,
	}

	gas := gasForContract(ctx)
	res, gasUsed, execErr := k.wasmer.IBCChannelClose(codeInfo.CodeHash, params, channel, prefixStore, cosmwasmAPI, querier, ctx.GasMeter(), gas)
	consumeGas(ctx, gasUsed)
	if execErr != nil {
		return sdkerrors.Wrap(types.ErrExecuteFailed, execErr.Error())
	}

	// emit all events from this contract itself
	events := types.ParseEvents(res.Attributes, contractAddr)
	ctx.EventManager().EmitEvents(events)

	if err := k.messenger.Dispatch(ctx, contractAddr, contractInfo.IBCPortID, res.Messages...); err != nil {
		return err
	}
	return nil
}

// OnRecvPacket calls the contract to process the incoming IBC packet. The contract fully owns the data processing and
// returns the acknowledgement data for the chain level. This allows custom applications and protocols on top
// of IBC. Although it is recommended to use the standard acknowledgement envelope defined in
// https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#acknowledgement-envelope
//
// For more information see: https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#packet-flow--handling
func (k Keeper) OnRecvPacket(
	ctx sdk.Context,
	contractAddr sdk.AccAddress,
	packet wasmvmtypes.IBCPacket,
) ([]byte, error) {
	contractInfo, codeInfo, prefixStore, err := k.contractInstance(ctx, contractAddr)
	if err != nil {
		return nil, err
	}

	env := types.NewEnv(ctx, contractAddr)
	querier := QueryHandler{
		Ctx:     ctx,
		Plugins: k.queryPlugins,
	}

	gas := gasForContract(ctx)
	res, gasUsed, execErr := k.wasmer.IBCPacketReceive(codeInfo.CodeHash, env, packet, prefixStore, cosmwasmAPI, querier, ctx.GasMeter(), gas)
	consumeGas(ctx, gasUsed)
	if execErr != nil {
		return nil, sdkerrors.Wrap(types.ErrExecuteFailed, execErr.Error())
	}

	// emit all events from this contract itself
	events := types.ParseEvents(res.Attributes, contractAddr)
	ctx.EventManager().EmitEvents(events)

	if err := k.messenger.Dispatch(ctx, contractAddr, contractInfo.IBCPortID, res.Messages...); err != nil {
		return nil, err
	}
	return res.Acknowledgement, nil
}

// OnAckPacket calls the contract to handle the "acknowledgement" data which can contain success or failure of a packet
// acknowledgement written on the receiving chain for example. This is application level data and fully owned by the
// contract. The use of the standard acknowledgement envelope is recommended: https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#acknowledgement-envelope
//
// On application errors the contract can revert an operation like returning tokens as in ibc-transfer.
//
// For more information see: https://github.com/cosmos/ics/tree/master/spec/ics-004-channel-and-packet-semantics#packet-flow--handling
func (k Keeper) OnAckPacket(
	ctx sdk.Context,
	contractAddr sdk.AccAddress,
	acknowledgement wasmvmtypes.IBCAcknowledgement,
) error {
	contractInfo, codeInfo, prefixStore, err := k.contractInstance(ctx, contractAddr)
	if err != nil {
		return err
	}

	env := types.NewEnv(ctx, contractAddr)
	querier := QueryHandler{
		Ctx:     ctx,
		Plugins: k.queryPlugins,
	}

	gas := gasForContract(ctx)
	res, gasUsed, execErr := k.wasmer.IBCPacketAck(codeInfo.CodeHash, env, acknowledgement, prefixStore, cosmwasmAPI, querier, ctx.GasMeter(), gas)
	consumeGas(ctx, gasUsed)
	if execErr != nil {
		return sdkerrors.Wrap(types.ErrExecuteFailed, execErr.Error())
	}

	// emit all events from this contract itself
	events := types.ParseEvents(res.Attributes, contractAddr)
	ctx.EventManager().EmitEvents(events)

	if err := k.messenger.Dispatch(ctx, contractAddr, contractInfo.IBCPortID, res.Messages...); err != nil {
		return err
	}
	return nil
}

// OnTimeoutPacket calls the contract to let it know the packet was never received on the destination chain within
// the timeout boundaries.
// The contract should handle this on the application level and undo the original operation
func (k Keeper) OnTimeoutPacket(
	ctx sdk.Context,
	contractAddr sdk.AccAddress,
	packet wasmvmtypes.IBCPacket,
) error {
	contractInfo, codeInfo, prefixStore, err := k.contractInstance(ctx, contractAddr)
	if err != nil {
		return err
	}

	env := types.NewEnv(ctx, contractAddr)
	querier := QueryHandler{
		Ctx:     ctx,
		Plugins: k.queryPlugins,
	}

	gas := gasForContract(ctx)
	res, gasUsed, execErr := k.wasmer.IBCPacketTimeout(codeInfo.CodeHash, env, packet, prefixStore, cosmwasmAPI, querier, ctx.GasMeter(), gas)
	consumeGas(ctx, gasUsed)
	if execErr != nil {
		return sdkerrors.Wrap(types.ErrExecuteFailed, execErr.Error())
	}

	// emit all events from this contract itself
	events := types.ParseEvents(res.Attributes, contractAddr)
	ctx.EventManager().EmitEvents(events)

	if err := k.messenger.Dispatch(ctx, contractAddr, contractInfo.IBCPortID, res.Messages...); err != nil {
		return err
	}
	return nil
}
